1. Field of the Invention
The present invention relates to a power control system, and more particularly, to a power control system capable of balancing output currents.
2. Description of the Prior Art
Among electronic products, magnitudes of input voltages required for circuits and blocks are not entirely the same. Therefore, a circuit system of an electronic product has to include a power circuit capable of modulating output voltage. In prior art, power circuits utilized for modulating output voltages are roughly classified into two types including switching circuits and linear power circuits, the linear power circuits are also denoted as linear voltage step-down circuits.
High transformation efficiency is a benefit of switching circuits, however, high design complexity and high costs are also drawbacks to switching circuits. The circuit design of a linear power circuit is simple, but has the drawback of low efficiency. The low efficiency of linear power circuits results from the fact that elements of linear power circuits consume redundant power in the form of heat. While the linear power circuits output higher power, the elements of linear power circuits may break down because of being overheated. Moreover, equipping the elements of linear power circuits with radiators not only increases costs, but also occupies additional space in the electronic products.
For overcoming the defect that the elements of linear power circuits become overheated, a solution is provided in the prior art. The solution includes parallel connecting or serially connecting multiple elements in linear power circuits for sharing output power respectively and lowering quantities of heat generated from each element. The multiple elements may be power resistors and power diodes. However, there may be slight differences between the multiple elements, causing it to be difficult to precisely control the power shared by each element.